Ivanov's famously disastrous premiere, in which the drunken actors forgot many of their lines, seems to have set its reputation as a minor Chekhov play. It's seldom staged, and is generally seen as merely a sketch of the genius better realised in masterpieces like The Seagull or The Cherry Orchard.

Watching this wonderful production, I couldn't help pondering the justice of this judgment: Ivanov seems rather more than a sidenote. It displays Chekhov's dispassionate accuracy of observation, a comedic eye for social detail as surgical as Jane Austen at her most caustic; and equally his instinct for the drama of human contradiction, if perhaps less nuanced than in his later plays. And beneath his art is already his fiercely moral refusal to judge weakness and folly, his sceptical idealism, his intense awareness of human possibility and finitude.

Chekhov himself said, in one of his many moments of irritation with the theatre: "In Ivanov it seems that I did not write what I wished. Remove it from the boards. I do not want to preach heresy on the stage. If the audience will leave the theatre with the conviction that Ivanovs are scoundrels and that Doctors Lvov are great men, then I’ll have to give up and fling my pen to the devil." But his frustration is as much with the limitations of theatre culture itself, as with his own abilities: " If the public does not understand 'iron in the blood'," he said, "then to the devil with it, i.e., with the blood in which there is no iron."When Chekhov's plays were premiered, his refusal to play to expectations obscured the perception of his work - Ivanov was called "brashly cynical, immoral trash" by a Moscow critic, who no doubt was looking for some clear moral judgment - a clearly "good" and "evil" axis in the play's human universe. This was something Chekhov explicitly refused to supply.

He was in the invidious position of someone attacking the very orthodoxies that obscured the perception of his own work, the conventional perceptions that made his achievement, literally, almost impossible to see. If a theatre is understood only in terms of generalised conventions, then what Chekhov creates can only be puzzling. Is it comedy? But the events are tragic... - But how can it be a tragedy, if parts of it are broadly hilarious? Where can the audience place its moral sympathy, if there is no clear moral? And so on...

In a theatrical culture dominated by melodrama, when complex characters like Chekhov's were virtually unprecedented on the stage, these responses might be predictable. They seem more difficult to understand now: but the fact remains that Chekhov is one of the most consistently misunderstood of modern playwrights. He is generally regarded as either the warm-hearted creator of absurdly loveable, stoic characters, or as a gloomily depressive Russian. He is much more interesting, of course, than either of these reductive caricatures. It is difficult, for example, to imagine Beckett without Chekhov to precede him.

The bafflements of Ivanov continue with its contradictory formalities: its shifts to melodrama or burlesque comedy are commonly perceived as flaws that compromise its serious intentions and disrupt its dramatic unity. Ariette Taylor's direction has the singular virtue of having ignored these "problems", simply presenting Ivanov as beautifully as possible, in all its variation of texture. And the production demonstrates that these are not flaws at all: as Peter Brook said, the central mechanism of theatre is contrast, and Chekhov grasped this principle surely and subversively.

Ivanov does lack the subtle nuance and flow of the later plays, though it certainly plays well enough. The company has resisted the temptation to cut the play to make it more palatable for contemporary audiences, and the dialogue has a robust colloquial vitality. However, it does remove a literary dimension that points to one of the romantic stereotypes that Chekhov sought to attack in his almost clinical depiction of Ivanov's depression: most of the references are gone that place Chekhov's portrayal of Ivanov as "superfluous man" in a tradition that includes Hamlet and Byron's Manfred - the misunderstood intellectual paralysed by melancholia.

And if the play also fails to reach the masterful, anguished poetry of key moments in Uncle Vanya or The Seagull, it has intriguing foreshadowings of the moral complexities that exist within them. Think of Nina's monologue in The Seagull : "I know now, I understand. - In what we do... the most important thing isn't fame or glory or anything I used to dream about - but the ability to endure. To know how to bear your cross and have faith. I have faith...and when I think of my vocation, I am not afraid of life..."

Unlike Nina or Sonya in Uncle Vanya, and like Treplyov, the writer who shoots himself in The Seagull, Ivanov is a man unable to endure. He cannot achieve the heroically existential faith which, in Chekhov's world, is the other side of despair. Ivanov is a idealistic aristocrat, a man who has married unconventionally, who has "tilted at windmills", rebelled against the banality and injustice that surrounds him. But now he is broken, caught in an inanition he is powerless to dissipate and cannot understand.

As played by Paul English, Ivanov is not only a man in the grip of spiritual exhaustion and depression, destroyed by the thousand cuts of the small-minded society in which he lives: he is also a victim of his own corrosive honesty. He is unable to deceive himself about either his condition or his feelings, and his inability even to manage the small deceptions that would comfort his dying wife Ana (Helen Morse) plunges him into a abyss of sick self-contempt.

His direct reflection is Lvov (Dan Spielman, looking unsettlingly like the young Chekhov), the young doctor whose honesty is a parade of certainties. To Lvov, good and evil are measurable and perceptible qualities. "How easy and straightforward," Ivanov protests towards the end of the play, as Lvov condemns him as a dishonest, evil hypocrite: "Man is such a simple and uncomplicated machine. No doctor... I don't understand you, you don't understand me, and we don't understand ourselves..."

This human opacity is what Lvov - and, by extension, Chekhov's imperceptive audiences - cannot admit. More explicitly than any other Chekhov play, Ivanov concerns itself with the idea that human certainty is the straightest road to blindness and folly; a telling stage direction in this particular dialogue is Lvov's refusal to listen. He knows, so he does not need to listen; to listen, indeed, might open him to unsettling possibilities about his own motivations (a subterranean desire, perhaps, for Ana) or make him see the vanity and destructiveness of his self-bruited "honesty".

But no one in this play is free from blindness: Ivanov is admirable only because he is the character with most self awareness, although it is no help to him. The complexities of the many characters are revealed in this production by a sheaf of intelligent and felt performances, both major and minor. There are a couple of electric scenes between Paul English and Helen Morse as Ana which made the hair stand up on my neck: what becomes palpable is the love that still exists between them, despite Ivanov's depression and guilt, despite the sudden gulf of despair which opens beneath Ana's poignantly self-controlled dignity. In another wrenching scene, Lebedov (Malcolm Robinson), Ivanov's debtor and friend, attempts to help him, fumbling past his futility and weakness to a raw expression of love.

Sascha, the young woman who deludes herself that she can save Ivanov by loving him, is played with a steely wit by Chloe Armstrong, surely one of the most under-estimated young actors in Melbourne. She saves the character from what otherwise might become a cloying sentimentality by investing the role with a sharp, ironic passion. It becomes clear that Ivanov's rejection of Sascha's love is clear-sighted: she does not love Ivanov himself, but what he represents to her, in the stifling and sexist society in which she lives: a chance to use her intelligence and vitality to some good end, not so far, perhaps, from Ivanov's desire to help the peasants. Dan Spielman as Lvov has possibly the most difficult part; it is challenging to play a prig and make him interesting, and Lvov's explosions of loathing are the only clue to his hidden inner life. For all the kinetic passion of his performance, I'm not sure that Spielman has yet quite grasped the character's full dimensionality; he seems curiously constrained, oscillating between the polar opposites of loathing and self-important righteousness. Perhaps as the season unfolds, more subtleties will emerge.

These intensities are leavened by some high comedy, provided in particular by the expansive energy of Alex Menglet as Shabelsky, Ivanov's uncle, an intriguing (and in Menglet's hands, very Russian) mixture of melancholia and extroversion; and by Stuart Morritt's irrepressible Borkin, the charmingly fraudulent manager of Ivanov's estate. These are huge performances which ignite the stage with an irresistible physical energy.

The smaller roles of Zinaida, Lebedev's miserly wife (Margaret Mills), Babakina, the wealthy widow (Jane Nolan), the old busybody Avadotia (Monica Maughan) and Kosich, an indefagitable cardplayer (Bob Hornery) people the production with polished comic performances. They devastatingly portray the venal, petty materialism which destroys Ivanov's idealistic attempts to change the world: yet in their individual particularities, their absurdities are also almost touchingly transparent. A nice touch, further enriching the dynamic texture of the production, is the presence of mute performers: in particular, the dancers Laurie Bishop and Jonathan Taylor, who play the ever-present but - to the characters - invisible servants, enacting their own trivial comic dramas.

Taylor choreographs her cast with a satisfying attention to both perspective and intimacy. The design is minimal and elegant: a drawing room, for example, is evoked by a single chandelier, or a garden by a pattern of leafy shadow. The actors are dressed in period costumes in a lush palette of autumnal colours, and the objects used on stage - decanters, antique tables and chairs, lace cloths - are focused by their contrast with the cool white walls of the space. At times the action is brought right up next to the audience: you might almost be sitting at the same dinner table as the characters, craning around someone's back to see the person opposite. In other scenes, chilly distances open between the characters, and between them and the audience.

The sheer energy on stage, the varying intensities of each moment, mean that the three hours of Ivanov fly past. It's a joy to see theatre like this. This production has many virtues, but perhaps its greatest is the sheer depth of its cast: the kind of insight an ensemble of this quality can collectively bring to a text can be revelatory.

People speak easily about the poetry of theatre, as if it were self evident, as if it were merely an ornament available to those who might choose to employ it. But poetry is not an easy thing. It is the pith and passion of plays, the molten spine of them; it is the profundity that is summoned by the carnality of language, the mystery of the corporeal and the mortal: this particular body in this specific time, speaking what cannot be repeated.

The Black Swan of Trespass and Stalking Matilda are very different plays; but both have been described as "poetic". It must be said that the poetry of theatre differs, markedly and importantly, from poems: but it is also related, in ways which are not necessarily obvious but which remain profound. Predictably I suppose, given my own predelictions, what struck me in both productions was a conviction that theatre practitioners would benefit from a better understanding of poetry.

The Black Swan of Trespass concerns itself with one of the most celebrated hoaxes in Australian literary history. In 1943 Harold Stewart and James McAuley, two poets with a particular animus towards the modernist work of writers like Dylan Thomas and Henry Treece, cooked up a fictional poet called Ern Malley. They created his life's work (sixteen poems called The Darkening Ecliptic) in an afternoon's hijinks of creative collage using, among other things, a Complete Works of Shakespeare and an army training manual on mosquitos. They concocted a letter from Ern's sister Ethel that described his life as a garage mechanic and his tragic early death from Graves disease, and sent the lot to Max Harris, then the young, iconoclastic editor of the modernist journal Angry Penguins.

As is well known, Harris enthusiastically published the poems, proclaiming Malley a genius. When Stewart and McAuley exposed the hoax, he stuck to his guns; whether or not they had intended it, he said, the poems were still extraordinary. But the story took another twist when Harris was prosecuted for obscenity in a courtcase which has shades of Pythonesque black comedy. The ultimate irony is that the poems have passages of undeniable beauty, and are now probably the most famous pieces of writing either Stewart or McAuley published. Malley generated a compelling reality: there is even a celebrated portrait of him by Sidney Nolan.

In The Black Swan of Trespass, writer Lally Katz and director Chris Kohn conjure some charming theatre from the ghostly figure of the imaginary poet. Ern Malley is summoned by Stewart and McAuley, who are represented by comically grotesque puppets - a chicken and a cat - on either side of the stage, and Ern himself (Christopher Brown) stands before us, tall, rangy, surreally Australian, all his suburban pathos framed in the velvet curtains of a puppet theatre.

The irony of Malley's situation as a poet who does not exist is not lost on him. As a theatrical creation, he is uneasily aware, as in fact any conscious writer must be, that his language is at best only partly his own and may be, in fact, writing him, that his writerly self is a fiction that trespasses hesitantly on the "alien waters" of reality. As the poet says in Dürer: Innsbruck, 1495, the work from which the show takes its title and which is to my mind the loveliest of the Malley poems:

"I had read in books that art is not easy But no one warned that the mind repeats In its ignorance the vision of others. I am still The black swan of trespass on alien waters."

The theatrical realisation of these complexities is often enchanting. Chris Kohn employs music, stylised performance and projected text as well as an ingeniously surreal design to create a show that works on multiple levels, and which seeks to express the pathos and irony of both Malley's unstable existence and his writings. Characters which are imaginary even in Ern's reality - Anopholes (Gavan O'Leary), a kind of mosquito-muse/narrator, and Princess (Jacklyn Bassanelli), his Keatsian love object - thicken the texture further. There are moments in this show - most often when Malley says his own poems - when all these complexities fold together into a shimmering, vital present.

One such scene is when Ethel (Katie Keadie) and Ern venture out into the real world, and speak about the people hurrying home - a description reminiscent of John Brack's painting Collins St, 5pm. Here the force of their yearning to be like other people, to be real, attains a potent and fragile poignancy. But too often this delicacy and poise is blurred in Lally Katz's script, which cannot but suffer by comparison to the complexity of the Malley poems: sometimes merely simplistic in its responses to them, it often veers dangerously close to sentimentalisation.

In the final scene, where Ern speaks his Petit Testament, I writhed at the bad judgement of punctuating each verse with lyrics from a sentimental love song. It was as if the dislocations of the poem, the contradictions of the poet and the poetry itself, could be resolved through a comfortingly simple narrative of unattainable and tragic love. No, it's not that simple.

Tee O'Neill's Stalking Matilda, directed by Chris Bendall for Theatre@Risk, addresses a more familiar theatrical poetic, that of the chorus. But this chorus is not a formal Greek convocation of witnesses, but something more like Brecht's idea of epic theatre in his essay The Street Scene, in which members of the cast enact the events they are describing, fluidly moving in and out of character.

Stalking Matilda was originally commissioned in Ireland, and has apparently been rewritten to reflect "an Australian setting and spirit". Perhaps its first problem is that, despite its concern with the plight of asylum seekers, common to both countries, it does not easily make the transition from Ireland to Australia. Local conditions, I couldn't help reflecting as I watched, do count; the English/Irish "hoodies" are not the same as Australian gangs; we have not had a celebrated racist murder like the Stephen Lawrence case in England (obliquely referred to in the play); and racism here is, if equally ugly, different in its ugliness.

The major difference between Ireland and Australia is perhaps that Australian history since settlement has been characterised by successive waves of immigrants and so is, whether we admit it or not, deeply multicultural, whereas Ireland is a racially homogenous society marked more by emigration than immigration, in which the sudden intrusion of "aliens" registers as a shock. The notion of "aliens" - central to the metaphor of the play - is somewhat muffled here by the immigrant status of so many of us. This uneasiness of locale undermines the play's potency; it might have been better to present it in its full Irishness.

Despite this, there is much to like in O'Neill's writing, in particular her robust embrace of human complexity and her refusal of easy moralising. The dilemmas faced by asylum seekers are sketched briskly and without sentiment. O'Neill portrays the injustices they face, desperately fleeing their own countries only to become persecuted non-citizens in a country that does not want them, but she also reveals the resilience and comic subversiveness of the oppressed, the small but vital ways in which human beings can help each other survive.

Central to the play is the figure of Matilda (Jude Beaumont), a charismatic, beautiful woman whose decision to walk into the sea and disappear is the mystery that sparks the action. The chorus - Irene Dios, Odette Joannidis, Ron Jordan, Toby Newton and Jeremy Stanford - discover her mobile phone on the beach and read a series of text messages, which reveal complexities, hypocrisies, strange elisions. The play is structured around a gradual enactment - not necessarily in chronological order - of the events that led to those cryptic notes.

Matilda is in many ways a symbol of European liberal ambivalence and its inevitable complicity with power. On the one hand, she is devoted to helping her asylum seeker friends, getting them false documents, spending hours with them in the bureaucratic maze of applying for citizenship, celebrating with them their small triumphs, even marrying Suleyman (Rob Jordan), a refugee from an unnamed African country. (Although ethnicities - Eastern European, African - are broadly suggested, countries are referred to by number - "First World", "Sixteenth World" - which is an economical and effective distancing device).

On the other, Matilda has a perverse affair with the General (Jeremy Stanford), a shadowy and sinister military commander who puts money into her bank account after every sexual encounter. And she may be also responsible for the death of Suleyman, who appears to be the victim of a brutal race hate crime, and for the burning down of the boarding house where her immigrant friends live.

The chorus sets off to discover the truth of these contradictory signs, but the murder mystery impulse isn't enough to sustain the energy of the play, despite a gallery of skilfully drawn characters and some interesting scenes. On the night I saw it, the action flagged considerably in its second half; it was a bit of a race to see whether the play would end before I lost interest entirely in why Matilda had walked into the sea. Jude Beaumont turning in anguish to the waves became, in truth, a rather over-used image during the course of the show. Though, in mitigation, I note that the given running time is 90 minutes, and the show I saw went for two hours. It could have been an exceptionally slow night that exaggerated the longeuers and repetitions in the production.

But there were other problems that were not to do with pacing. Especially towards the end, the chorus was often written with a self-conscious, literal clumsiness that slowed down the play. The physical-theatre aspect of the performances, together with the day-glo circus set, at times reminded me of those breathlessly earnest Theatre In Education shows English teachers used to inflict on unwitting adolescents in the name of culture. At its best, the production transcended these associations, but not often enough to lift the show out of its problems.

There is a poetic of a promising muscularity at work in this play, but it stumbles. Poetry exists in the silences between words, in what is not said, at least as much as it does in the words spoken; and sometimes in Stalking Matilda there were just too many notes.